Re: iteration thru makefile reloading

[Ken Smith]

(reincluding the list, comments inline)

On 12/26/06, Kevin Route <address@hidden> wrote:
> On 12/25/06, Ken Smith <address@hidden> wrote:
> > On 12/25/06, Kevin Route <address@hidden> wrote:
> > > I am trying to create a makefile that will auto-discover dependencies by
> > > using what I call "iteration thru makefile reloading" (no recursive
> make).
> >
> > I played with your makefile for a bit and, after watching it do what I
> > think its trying to do, I'm puzzled as to why you choose this
> > approach?
>
>  Well, like you suspect it, my concern is not about the c0 to c5 files, I
> only added this
>  $(shell ....) in oder to have a "self sufficient" makefile.... and I didn't
> want this to interfere with
>  the dependency graph......
> >   During my investigation, I came up with this
> > reimplementation that superficially does something like your original.
[clip]
>  Ok, I will try....

>  These old c (config) files contain "dependency information" I try to get
> (automatically) into my "new" make system.
>
>  for example:
>     package-X,version-R
>  contains
>    needed := package-Y,version-S  package-Z,version-T

Ok, lets take these files for granted but make them in a separate demo file.

---BEGIN prep.mk---
$(shell \
 echo "needed := p2,v1" > 'c1,v1'; \
 echo "needed := p3,v1 p4,v1" > 'c2,v1'; \
 echo "needed := p4,v1" > 'c3,v1'; \
 echo "needed := " > 'c4,v1' ; \
)
---END prep.mk---

If each file contains a list of dependencies and the variable they
each declare is called "needed", I still advocate $(foreach) over
automatic reinvocation of make.

---BEGIN GNUmakefile---
$(foreach inc,$(wildcard c*), \
 $(warning processing dependency file $(inc)) \
 $(eval include $(inc)) \
 $(foreach dep,$(needed), \
   $(warning $(inc) needs $(dep)) \
  ) \
)
---END GNUmakefile---